1. Field
Apparatuses and methods consistent with exemplary embodiments relate to a digital broadcast transmitter, a digital broadcast receiver, and audio description descriptor processing methods thereof, and more particularly, to a digital broadcast transmitter which transmits an audio description descriptor including auxiliary information, a digital broadcast receiver which receives and processes the audio description descriptor, and audio description descriptor processing methods of the digital broadcast transmitter and the digital broadcast receiver.
2. Description of the Related Art
With the spread of digital broadcasting, an increasing number of electronic devices have been designed to provide digital broadcast services. Not only home-base devices, such as a digital television (TV), a set-top box, etc., but also mobile devices, such as a mobile phone, a navigation device, a Personal Digital Assistant (PDA), an MP3 player, etc., have been equipped with a function to support digital broadcast services.
Digital broadcasting is a type of broadcasting, which is characterized by digitally compressing a broadcast signal and transmitting the digitally-compressed broadcast signal. Digital broadcasting can allow multiple videos or audios to be compressed and transmitted without any quality degradation.
Digital broadcasting may provide audio descriptions to help, for example, the visually challenged, to better understand the content of each broadcast program. The term “audio description” may indicate an audio output of the title of a broadcast program or a narrated presentation of the content of the broadcast program. That is, an audio description may correspond to an auxiliary audio signal. For example, when a video message “Kildong Hong, the mayor of Seoul” is displayed on a screen, a corresponding audio message may be output as an audio description.
An audio description may be included in a digital broadcast program along with an audio description descriptor indicating whether the digital broadcast program includes any audio description. FIG. 11 illustrates the configuration of a related-art audio description descriptor.
Referring to FIG. 11, the related-art audio description descriptor is simply used to transmit information relating to an audio description, such as, whether to apply effects, such as “fade” and “pan,” to the audio description, and may be considered inefficient because it often includes too many reserved fields that are not much of use.
Therefore, there is a need for methods to make efficient use of an audio description descriptor.